Researchers claim to have produced sought-after quantum effect.
Geoff Brumfiel

A team of physicists is claiming to have coaxed sparks from the vacuum of empty space. If verified, the finding would be one of the most unusual experimental proofs of quantum mechanics in recent years and "a significant milestone", says John Pendry, a theoretical physicist at Imperial College London who was not involved in the study.

The researchers, based at the Chalmers University of Technology in
Gothenburg, Sweden, will present their findings early next week at a workshop in Padua, Italy. They have already posted a paper
on the popular pre-print server arXiv.org, but have declined to talk to
reporters because the work has not yet been peer-reviewed. High-profile
journals, including Nature, discourage researchers from talking to the press until their findings are ready for publication.

Nevertheless, scientists not directly connected with the group say
that the result is impressive. "It is a major development," says
Federico Capasso, an experimental physicist at Harvard University in
Cambridge, Massachusetts, who has worked on similar quantum effects.

At the heart of the experiment is one of the weirdest, and most
important, tenets of quantum mechanics: the principle that empty space
is anything but. Quantum theory predicts that a vacuum is actually a
writhing foam of particles flitting in and out of existence...